Photographs taken near the type locality show a uniform sandy bottom with ripple marks.

Distribution: In addition to the type-locality, other nearby station collections contained A. subellipticusspecimens, viz. Eltanin Stations 120, 1 male 2.0 mm long (deposited in the AHF) ; 155, 2 males 2.2 and 2.0 mm and 1 female 2.4 mm long (USNM 113325) ; and 394, 2 females 2.6 and 2.0 mm long (USNM 113326) . All four stations, including the type-locality, are off the tip of South America.

Affinities: The new species differs from A. armatusin the shape of the rostrum and the shape of the pos­terior part of the pleotelson. The new species also differs from A. armatusin the shape of the posterior part of the pleotelson (which is similar in other re­spects also) and in the shape of the anterior margin of the cephalon. The regularly rounded convex lateral borders of the whole body set the species apart from other Antennuloniscusspecies.”